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history of Central Intelligence Agency

...for the collection of secret information for policy makers. Indeed, prior to 1942 the country lacked any civilian intelligence agency. Information was collected in an unsystematic way by the
Office of Naval Intelligence, by U.S. Army intelligence, and by the FBI. The information gathered was rarely shared with other government agencies and was sometimes not even provided to senior policy...

structure of intelligence operations

...each of them continues to perform significant tactical and technical intelligence and counterintelligence activities. Army intelligence is headed by the deputy chief of staff for intelligence. The
Office of Naval Intelligence (ONI), headed by the director of naval intelligence, is responsible for foreign intelligence and cryptology. Air Force intelligence is headed by the director of...